"Whether you run a small business or large corporation
-- or just have a desktop PC at home -- if you're connected to the
Internet for any amount of time, you need a firewall to keep your
data safe. People with ill intentions will try everything from
stealing your credit card data, to exploiting open mail relays for
spam, or even manipulating potential (and unwitting) participants
in Distributed Denial of Service (DDoS) attacks.
You must decide what kind of firewall you need, and whether you
want to set it up yourself from scratch or have a little help. It's
certainly possible to install just about any Linux distribution, or
one of the *BSDs, and configure that to run as a firewall. For the
more technically inclined, it's not difficult. However, most of us
would rather spend our quality time doing something other than
configuring a firewall from scratch.
I've taken a look at two commercial Linux products (SuSE
Firewall on CD and Mandrake Single Network Firewall) and one of the
most popular non-commercial firewall distros (Coyote Linux) to see
what features and options they offer. Each of these firewall
distributions is based on the 2.2.19 kernel, and they're all
IPChains-based. But that's where the similarities end. The
installation and setup procedure for each distro is unique, and
each one has features that make it perfect for some applications
and not suitable for others."